Ignition switch question

[wingnut62]

I am having a heck of a time establishing my accessory position on my ignition switch. It's a stock 65 switch, i have hunted every connection on it for continuity between the power and the acc connector with the key in the acc position.

Thinking my switch was faulty I drove to H&H Classic parts and their switch did the exact same thing. I am not a novice tech guy my any stretch, did the entire wire harness for the LS in it, wired all else up so I know my way around the electrical circuit. This one however has me bumfuzzled.

Am I supposed to get voltage at the acc conductor on the switch when in the ACC position with the key? Any help, suggestions, comments would be appreciated. I really don't want to run a separate switch for accessory power.

[vin63]

The ACC position on my factory switch didn't work (I think it is more of a lock than ACC), nor any of the OE replacement switches I tried. I know that doesn't help, but I have had the same experience.

[wingnut62]

Vin63, thanks for the response. I figured as much since I checked/verified with a new OTB switch. That sux really. The only way we can listen to the sound system is to have the key in on posit which has the fuel pump running and the PCM hot. Not sure if that is a bad thing as the FP shuts off after a few seconds, maybe I am just thinking back on the old points ignition days where they could actually weld shut if the key was left on.

Guess I will have to install a secondary toggle for acc.

p.s. I like your signature block, I drove FED's a few years back. Loved em, miss em still.

Ken

[ray_mcavoy]

The factory ignition switches in these trucks did not have an accessory position. They have an "ACC" terminal on them but that will only have continuity to the "BAT" terminal when the switch is in the "on" position.

I think it was mid-year 1968 or so before GM started using ignition switches with an accessory position in the trucks. However, the ignition switches in many early/mid 60's GM cars did have an accessory position and use the same electrical connector as the truck switches. So changing over to a car ignition switch might be an option for you.

[Cooper197]

My switch, which may very well be a replacement, does have an accessory position. You turn the key to the left instead of to the right. My dad's 64 does this too. I just rewired my truck and confirmed that the accessory terminal is powered both on the accessory position and ignition position, as it should be. The ignition terminal is just powered on the ignition position not on accessory, again as you would expect.

[ray_mcavoy]

Originally Posted by Cooper197

My switch, which may very well be a replacement, does have an accessory position. You turn the key to the left instead of to the right. My dad's 64 does this too.

Yeah, that sounds like both your trucks have replacement GM car style ignition switches. With the car switches, turning them to the left (counterclockwise) from the off/lock position puts them into the accessory position where only the "ACC" (and not the "IGN") terminal is powered.

Here's a scan from the '66 Chevy Truck owner's manual showing only 3 positions (off, on, and start) on the factory truck ignition switches:

[wingnut62]

Originally Posted by Cooper197

My switch, which may very well be a replacement, does have an accessory position. You turn the key to the left instead of to the right. My dad's 64 does this too. I just rewired my truck and confirmed that the accessory terminal is powered both on the accessory position and ignition position, as it should be. The ignition terminal is just powered on the ignition position not on accessory, again as you would expect.

Would you happen to have a part number or something I can go off of regarding your switch? I really want and need ACC on mine and it sounds like yours is the ticket.

thanks in advance

[The Rocknrod]

Some info on ignition switches - http://67-72chevytrucks.com/vboard/s...d.php?t=631725

[vin63]

I'm currently re-wiring my truck with a Ron Francis Express kit. I used several of the extra constant hot accessory terminals on the new fuse block for my radio, power windows, etc. I made a separate harness for the circuit for my fuel pump relays.

Originally Posted by wingnut62

Vin63, thanks for the response. I figured as much since I checked/verified with a new OTB switch. That sux really. The only way we can listen to the sound system is to have the key in on posit which has the fuel pump running and the PCM hot. Not sure if that is a bad thing as the FP shuts off after a few seconds, maybe I am just thinking back on the old points ignition days where they could actually weld shut if the key was left on.

Guess I will have to install a secondary toggle for acc.

p.s. I like your signature block, I drove FED's a few years back. Loved em, miss em still.

Ken

[wingnut62]

Yeah I really wanted the option of the radio turning off when the key went off. My wife will invariably leave it on when she gets out and you know what happens to the battery then.

[vin63]

That's the cool thing with those Select-a-Circuit accessory terminals on that Ron Francis block, and one of the reasons I like the RFW kits. You can reposition the fuse to make the circuit only hot when the ignition is on.

[61K10]

I have i think is a 63 Impla switch that has acc.